The commentary to ASCE 7 quantifies the intended performance for buildings in different Risk Categories. Below Table summarizes the anticipated reliability values. These values have not been validated with experience or in-depth analysis, but instead are notional values that represent the intent of 48 the building code committee. FEMA P-695 (2009) also suggests that the probability of collapse due to MCE ground motions should be limited to 10% for Risk Category II buildings. FEMA P-695 presents a detailed methodology for determining collapse probability of classes of buildings. Several case studies have used the methodology to benchmark performance of modern buildings, with results reported in FEMA P-695 (2009) and NIST (2010).
Firstly, ASCE 7-10, the earthquake design values for most locations in the United States have been adjusted so that structures having standard collapse fragility will have a collapse probability of 1% in 50 years.